In vitro Study of Percutaneous Absorption, Cutaneous Bioavailability and Bioequivalence of Zinc and Copper from Five Topical FormulationsPirot F. · Millet J. · Kalia Y.N. · Humbert P.
aDepartment of Functional Dermatology, University Hospital, and bLaboratory of Galenic Pharmacy, University of Besançon, France; cDepartment of Pharmacy, University of California, San Francisco, Calif., USA
Percutaneous absorption and cutaneous bioavailability of zinc and copper from zinc 2-pyrrolidone 5-carboxylate (ZnPC), zinc oxide (ZnO), zinc sulfate (ZnSO4), copper 2-pyrrolidone 5-carboxylate (CuPC) and copper sulfate (CuSO4) were compared using 5 formulations (3 emulsions and 2 ointments) that were applied topically on human skin in vitro. After application for 72 h, percutaneous absorption of zinc from ointments containing ZnO and ZnSO4 was found to be lower than that from a ZnPC-containing emulsion (0.36 and 0.34 versus 1.60% of applied dose). In the case of copper, the flux after a 72-hour treatment period showed that there had been minimal release from CuPC- and CuSO4-containing formulations (approximately 5 ng/cm2/h). All formulations used in this study effected an increase in zinc and copper concentrations in whole skin and epidermis. Bioequivalence of the 5 formulations based on pharmacokinetic results was assessed, and salt and vehicle effects were discussed.
F. Pirot, Department of Pharmacy, University of California, San Francisco, CA 94143 (USA)
Received: November 17, 1995
Accepted: March 13, 1996
Published online: March 31, 2009
Number of Print Pages : 11
Skin Pharmacology and Physiology (Journal of Pharmacological and Biophysical Research)
Vol. 9, No. 4, Year 1996 (Cover Date: 1996)
Journal Editor: Lademann J. (Berlin)
ISSN: 1660-5527 (Print), eISSN: 1660-5535 (Online)
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